The collision occurred at the corner of Lincoln Avenue and Pomona Road around 8:37 a.m.
Corona police Lt. Mark Johnson said the chain of events began after a caller dialed 911 and reported that a robber with a gun was leaving a motel near the area. The caller provided police with a description of the suspect and getaway car plate number.
An officer spotted the alleged robber's vehicle near Lincoln Avenue and Railroad Street and called for assistance.
The second officer, responding to the call, was involved in a collision with a second vehicle. It remains unclear if the police car had lights or sirens on.
A man and woman inside the second vehicle were transported to a local hospital with back pain.
Two men and a woman were arrested in connected with the armed robbery, Johnson said.
CNS contributed to this report.